Nixtamal has been the basis for the production of maize dough and its byproducts, as maize has been the major grain source in the Mexican diet. To make into dough, it is necessary to cook the partially dried maize grains. Traditionally, the method used was to add a minimum of 2% lime to water a clay pot and cook the mixture, after which time the maize is poured into huge vats and rinsed, a process which produces high amounts of toxic waste water. Once the maize is rinsed, the water drained, producing a high amount of toxic waste water. After having been cooled and rinsed, the grains are then ground. While this traditional method has been sufficient for supplying tortilla factories with maize dough to make tortillas, the tortilla factories, in order to save time and effort, the pots and vats they use are not maintained in proper sanitary conditions, due to various factors in the nixtamal cooking process, which lead to the accumulation of germs and bacteria over time in the large vats, making them hard to clean. Another unsanitary condition is the nejayote (cooking water) which contains lignin (a polymer present in the maize grain's cellular walls). Its basic pH is highly toxic but the wastewater is nevertheless discarded into the drainage system. Traditionally, nixtamal mills use a minimum of 2% lime in large vats of water to ensure that the maize is uniformly cooked (nixtamalization base) to produce the highest-quality nixtamal, but which leads to the disposal of large amounts of nejayote. So, the lack of control mechanisms in the maize mills has led to an industry based largely on price and maize quality speculation, thus influencing the price of tortillas, causing the prices to stagnate rather than lowering costs, while the quality of maize dough has gone down, not to mention the dough's hygienic standards.
Field technicians specialized in grinding and nixtamalifying maize are also familiar with the fact that sacks of maize that arrive to the mill often contain contaminants ranging from maize dust to dead animals, which often go undetected in the large quantities of nixtamal which pass through the mills on a daily basis, contaminants which may be passed on to consumers.
In the current stage of technological development, several large cooking vats have replaced the traditional pots in the nixtamal cooking process. Patent MX292580 is related to the tortilla industry and any new industry requiring the nixtamalization of any of its products. Specifically, this nixtamalization process involves a rotary reactor, and conditioning the grain before it is cooked and left to soak. This conditioning process consists of running the grains through a certain amount of water to hydrate the grain. Although the invention refers to a rotary reactor, this definition does not explain its entire function. Water vapor is also used to hydrate the grain before cooking, a process which uses a lot of energy and requires a large amounts of water, likewise producing more contaminants.
Most modern rotary reactors are laterally revolving concrete vats which require a series of internal blades to agitate its contents. These types of cooking vats have the unfortunate aspect of losing the necessary heat to maintain the nixtamalization process, resulting in a high-cost and inefficient system, as well as requiring large amounts of time and water to wash and sanitize the internal blades.
Systems for obtaining nixtamal are considered suitable for large industries which require cooking large amounts of product and thus necessitate alternative processes to cook maize according to necessary temperature changes, and by introducing water vapor to help hydrate the maize grain.
To understand how nixtamal works, it is necessary to note that it is a Mesoamerican technology: the maize is cooked with a given portion of lime (calcium hydroxide), usually three parts water for every party lime, or a little more if the maize grains are especially hard. Once it is cooked, the grain is preferably soaked overnight, while the soaking time may vary depending on how long the mixture has been cooked, but long enough for the skin to separate from the grain, hydrating the typically tough grain and making the maize easier to grind later. Based on this basic nixtamalization process, a range of byproducts are produced, which have yet to be eliminated from the process.
There are a number of necessary market elements in nixtamal production. In the first place, it is preferable for nixtamal to be in close proximity to tortilla factories, and even more preferable if the tortilla factors or other facilities using nixtamal are in a secure production chain involving grinding the nixtamal, does not take up a lot of space, and eliminates the amount of nejayote discarded. Above all, the production system should be easily and efficiently operated. This allows each point of operation utilizing nixtamalization to improve the quality of its products by eliminating the intermediary (maize mills), which may arbitrarily set the prices of the nixtamal and its byproducts to its own advantage. Technicians familiar with the process know that maize mills traditionally produce nixtamal, grind it, before finally transporting it to the tortilla factories, but that the product has an expiration period of 9 hours, and will be discarded if the product cannot be utilized within that time period. These losses are then directly reflected in the direct sales cost to the consumer. This also leaves the tortilla makers at a disadvantage because they cannot store the dough from the day before, making the tortilla manufacturer dependent on the maize mill's production cycles. In addition to being dependent on mill production, the tortilla makers cannot determine the quality of the dough or the maize used for making the tortillas, and moreover, have little control over the sanitary conditions of the process.
Another disadvantage in terms of transporting the nixtamal and dough is contamination en route, which in turn is passed along to the final consumer.